1. Field of the Invention
The invention relates to railway cars and particularly to connections of partition sheets at their vertical edge portions to side sheets.
2. Description of the Prior Art
The prior art includes partition sheets that divide covered railway hopper cars into compartments. The partition sheets are connected along their vertical edge portions to the internal side of side sheets. In the area of this connection, on the external side of the side sheet, is a hat shaped vertical side post. These side posts have their open portions abutting the side sheet.
Forces created during the coupling-uncoupling operation of railway cars and during acceleration cause loads which the partition sheets must restrain. To restrain these loads the partition sheet flexes, much like a membrane. As the partition sheet flexes a corresponding moment force is produced in the area of the partition sheet to side sheet connection. If as the partition sheet flexes, the side sheet rotates, stress build-up will be minimal. If not, stresses will build in the partition sheet at its connection to the side sheet, leading to fatigue fractures.
The hat shaped vertical side post with its open portion abutting the side sheet acts as a rotational stiffener to the side sheet in their area of contact. The side sheet is therefore restrained from rotating as the partition sheet flexes. This causes a high degree of stress concentration in the partition sheet in the area of its connection with the side sheet causing premature fatigue cracking under cyclic flexing.
The present invention is an improvement over the prior art by reducing the stress concentration in the area of the partition sheet connection to the side sheet. This is accomplished by replacing the hat shaped vertical side post in the area of the partition sheet connection with a stress reducing internal or external post member which provides less rotational restraint.